如何把picturebox里的图片存为JPG格式

[qq_15238669]

现在我可以存为.bmp格式，但是怎么样才可以存jpg格式呢，是不是需加载什么库？
注意是文件格式为JPG不是仅仅改一个后缀名

[良朋]

Me.PictureBox1.Image.Save("c:\abc.jpg", System.Drawing.Imaging.ImageFormat.Jpeg)

[llllinlink]

using System;
using System.Drawing;
using System.Drawing.Imaging;
class Example_SetJPEGQuality
{
    public static void Main()
    {
        Bitmap myBitmap;
        ImageCodecInfo myImageCodecInfo;
        Encoder myEncoder;
        EncoderParameter myEncoderParameter;
        EncoderParameters myEncoderParameters;
                     
        // Create a Bitmap object based on a BMP file.
        myBitmap = new Bitmap("Shapes.bmp");
                     
        // Get an ImageCodecInfo object that represents the JPEG codec.
        myImageCodecInfo = GetEncoderInfo("image/jpeg");
                     
        // Create an Encoder object based on the GUID
                     
        // for the Quality parameter category.
        myEncoder = Encoder.Quality;
                     
        // Create an EncoderParameters object.
                     
        // An EncoderParameters object has an array of EncoderParameter
                     
        // objects. In this case, there is only one
                     
        // EncoderParameter object in the array.
        myEncoderParameters = new EncoderParameters(1);
                     
        // Save the bitmap as a JPEG file with quality level 25.
        myEncoderParameter = new EncoderParameter(myEncoder, 25L);
        myEncoderParameters.Param[0] = myEncoderParameter;
        myBitmap.Save("Shapes025.jpg", myImageCodecInfo, myEncoderParameters);
                     
        // Save the bitmap as a JPEG file with quality level 50.
        myEncoderParameter = new EncoderParameter(myEncoder, 50L);
        myEncoderParameters.Param[0] = myEncoderParameter;
        myBitmap.Save("Shapes050.jpg", myImageCodecInfo, myEncoderParameters);
                     
        // Save the bitmap as a JPEG file with quality level 75.
        myEncoderParameter = new EncoderParameter(myEncoder, 75L);
        myEncoderParameters.Param[0] = myEncoderParameter;
        myBitmap.Save("Shapes075.jpg", myImageCodecInfo, myEncoderParameters);
    }
    private static ImageCodecInfo GetEncoderInfo(String mimeType)
    {
        int j;
        ImageCodecInfo[] encoders;
        encoders = ImageCodecInfo.GetImageEncoders();
        for(j = 0; j < encoders.Length; ++j)
        {
            if(encoders[j].MimeType == mimeType)
                return encoders[j];
        }
        return null;
    }
}

MSDN copy的==我也没试，你可以自己去看一下image类

[qq_15238669]

那如果碰到有重名图片吗 也就是实现存储覆盖功能怎么解决？ Me.PictureBox1.Image.Save只能保存无法实现另存为的覆盖功能

[llllinlink]

if(File.Exist(x.jpg))
{
File.Delete(x.jpg)
}
else
{
//Save
}

[jhonsonzhang]

using bmp as new bitmap(me.picturebox1.image.width,me.picturebox1.image.height) using g=graphic.fromimage(bmp) g.drawimage(me.picturebox1.image,0,0,bmp.width,bmp.height) end using bmp.save(decPath,imageformat.jpg) end using 没在开发机器上，凭印象打的，代码大致应该如此。

[清晨曦月]

引用 3 楼 qq_15238669 的回复:

那如果碰到有重名图片吗 也就是实现存储覆盖功能怎么解决？
Me.PictureBox1.Image.Save只能保存无法实现另存为的覆盖功能

那不是image.save函数管的，先自己检测是否有重名，根据savefiled...的filename再去设置save的path。

[data-v-165b75c4]

支持2#，没必要转换，自带功能